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Ok I have a 10 tooth cassette in the rear and i need to know what size chainring I need in the front to have a good ratio on my SS 29er.
In BMX a 10 tooth cassette is best paired with a 28 or 30 tooth sprocket but i dont know if its the same with 29er.
If it helps figure it out I have Truvativ Isoflow cranks. Dont know much. Anything would help. Thanks
 

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Come see me after class
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32:18 is the most common 29er gearing from the factory. to match that ratio with a 10T cog, you would need a 18T chainring, which just ain't gonna happen, even on the inner ring. you'll need to swap chainring and rear cog.

depending on your strength and terrain, your ideal gearing may be completely different from your next door neighbor. 32:18 works well for me and i live where it's pretty much flat, FWIW.
 

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a cassette is made up of multiple cogs. a BMX bike has a single cog (or "driver" as the BMX crowd calls them). how did you end up with a 10T cog on your 29er?

a 20T chainring would work, but they don't make any.
 

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if you're new to single speeding, i'd suggest at least 32:18 for a 29er. any taller and you'll be walking more than you're pedaling. if you have anything that resembles hill country, you'll want something like 32:20.

14t cog with a 32T ring will be brutal unless it's your commuter on slicks. so this begs the question: what kind of bike is this? is this a trail bike or a commuter?
 

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what's the chainline on this rear hub? There are rings that would fit the granny ring mounting holes (64mm BCD) from 20t up to at least 28t if I remember correctly, but the chainline is way off from many hub unless it is a larger freehub. Also a 20t usually requires grinding material off the crank so the chain can fit, and on the other end many frames are not designed to fit granny rings much larger than the standard size
 

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ImEvergreen17 said:
Any suggestions on single speed rear hubs. I need a single speed hub to change my crappy unsealed 9-speed hub with a single speed kit on it.
most of the best deals are on geared hubs and wheels, and IMHO there is nothing wrong with using spacer kits on a 9spd hub. I invested in a very nice rear hub on my SS and I went for a 9spd version because of the deal I got. No regrets there
 

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i would just get a new cog and maybe a new ring. what size is your middle ring? it's probably a 32T so all you would need is a new cog. you can get a shimano BMX cog for $5-10 shipped, from ebay.

what is your current setup? it's sounding like you have a bit of a frankenbike going on. i'm assuming you have a 10T cog on the back. how many rings does the bike have on it? does it have all three? which ring are you planning on using? (the middle ring is the most common.)
 

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alexrex20 said:
i would just get a new cog and maybe a new ring. what size is your middle ring? it's probably a 32T so all you would need is a new cog. you can get a shimano BMX cog for $5-10 shipped, from ebay.

what is your current setup? it's sounding like you have a bit of a frankenbike going on. i'm assuming you have a 10T cog on the back. how many rings does the bike have on it? does it have all three? which ring are you planning on using? (the middle ring is the most common.)
normal cassette hubs can only fit a 12t cog at the smallest, so he must have bought a BMX style hub that use a "driver" that is designed specifically for that hub.
 

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Probably a good idea to go to your Local Bike Shop (LBS) and work with the guys there to get a setup that is appropriate for your new location.
 
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